The present invention relates to a tow hook for a tractor and, more particularly to an attachment mount for a tow cable used on, but not limited to, an agricultural tractor.
Tow cables are often offered on tractors used in applications where the likelihood of becoming stuck is great. One typical application is the use of four-wheel drive (4WD) agricultural tractors to pull earth scraper pans. Extracting a stuck tractor and scraper pan subjects the tractor to large pulling forces as sometimes multiple tractors are used to extricate the stuck tractor and its connected implement. For convenience, many tractors of this type incorporate a length of tow cable which provides a convenient connection point on the stuck tractor. Such tow cables are anchored to a structurally robust portion of the tractor, generally on inaccessible lower portions of the tractor frame, and provide an easily accessible tow connection point near the front of the tractor. Due to the magnitude of the pulling forces required, a suitable attachment mount for the towing cable must be provided that is capable of withstanding the large forces and that transfers the pulling forces into a suitable frame structure on the tractor.
Ideally, a tow cable attachment point is provided proximate to the forward end of the drawbar so that pulling forces are generally directed through the portion of the tractor frame designed specifically for pulling loads. In this manner, pulling forces from the second tractor are directed to the drawbar of the first tractor which avoids using other portions of the tractor frame to transfer these forces. The STX and TJ series four-wheel drive tractors manufactured by Case New Holland are typical examples of tractors including this feature. Changes in the design of the drawbars used on the Case New Holland STX and TJ series tractors have rendered the previous tow cable attachment point unsuitable. Additionally, earlier tow cable attachment point designs connected directly to the drawbar subjected the drawbar attachment pin to reverse bending stresses which increases the likelihood of failure of the attachment pin.
In today's competitive market, functional performance using designs that are simple in construction is paramount. It would, therefore, be a great advantage to provide an improved attachment mount for a tractor tow cable that is durable when subjected to the towing forces, offers a generally direct load path between towing tractors and the draft load line of the stuck tractor implement combination, and relies on, to the extent practicable, existing structural framework on the tractor to overcome the above problems and disadvantages. Still more advantages would be realized if the attachment mount required no chassis design alterations and little or no modification of the tractor chassis.